52008

Appears in sequences

• Positive numbers k such that k*(k+1) is a palindrome.at n=9A028336
• Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 19.at n=11A031697
• Octagonal numbers which are the sums of exactly two positive octagonal numbers.at n=24A136346
• a(n) = 361*n^2 + 2*n.at n=11A158309
• Number of vertices in an equilateral triangle "frame" of size n (see Comments in A328526 for definition).at n=18A333031